diff --git a/34. One hot encoding.py b/34. One hot encoding.py
new file mode 100644
index 00000000..41c5e73c
--- /dev/null
+++ b/34. One hot encoding.py	
@@ -0,0 +1,15 @@
+import torch
+from typing import Optional
+
+def to_categorical(x: torch.Tensor, n_col: Optional[int] = None) -> torch.Tensor:
+    """
+    Perform one-hot encoding on a 1D integer tensor `x`. If `n_col` is not provided, infer it from the max value in `x`.
+    """
+    if n_col is None:
+        n_col = x.max().item() + 1
+
+    x = x.to(torch.long)
+    one_hot = torch.nn.functional.one_hot(x, num_classes=n_col)
+    one_hot = one_hot.float()
+
+    return one_hot